Plain computed tomography for differentiating neoplastic and non-neoplastic pedunculated gallbladder polyps.

AIMS: Surgery is recommended for large pedunculated gallbladder polyps (PGPs), which measure 10 mm or more in size, because they tend to be neoplastic polyps (NPs), such as adenomas and adenocarcinomas. However, after resection, they are often found to be non-neoplastic polyps (non-NPs). This study aimed to evaluate the usefulness of plain CT in distinguishing NPs from non-NPs. METHODS: Of the 80 patients who underwent cholecystectomy for PGPs ( 10 mm between January 2008 and February 2021, 46 who underwent plain and contrast-enhanced CT (CE-CT) before resection were included in this study. We retrospectively assessed the polyp detection rate (PDR) using CT and calculated the difference in the CT values between PGPs and the surrounding bile. RESULTS: Twenty-one patients had NPs (12 adenomas, 5 carcinomas in adenoma, and 4 adenocarcinomas). The others were non-NPs (24 cholesterol polyps and one hyperplastic polyp). The PDR using plain CT was significantly higher in the NP group than in the non-NP group (38% (8/21) vs. 0% (0/25), p <0.01). The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of NPs were 38%, 100%, 100%, 66%, and 72%, respectively. The difference in the CT values between PGPs and the surrounding bile was significantly larger in the NP group than in the non-NP group (14.12 ± 11.38 HU, 5.04 ± 6.15 HU, p <0.01). CONCLUSIONS: PGPs detected using plain CT had a high probability of being NPs. Plain CT is therefore considered to be useful for differentiating NPs from non-NPs.

Up-regulated expression of two-pore domain K+ channels, KCNK1 and KCNK2, is involved in the proliferation and migration of pulmonary arterial smooth muscle cells in pulmonary arterial hypertension.

Background: Pulmonary arterial hypertension (PAH) is a severe and rare disease in the cardiopulmonary system. Its pathogenesis involves vascular remodeling of the pulmonary artery, which results in progressive increases in pulmonary arterial pressure. Chronically increased pulmonary arterial pressure causes right ventricular hypertrophy and subsequent right heart failure. Pulmonary vascular remodeling is attributed to the excessive proliferation and migration of pulmonary arterial smooth muscle cells (PASMCs), which are induced by enhanced Ca2+ signaling following the up-/down-regulation of ion channel expression. Objectives: In the present study, the functional expression of two-pore domain potassium KCNK channels was investigated in PASMCs from idiopathic PAH (IPAH) patients and experimental pulmonary hypertensive (PH) animals. Results: In IPAH-PASMCs, the expression of KCNK1/TWIK1 and KCNK2/TREK1 channels was up-regulated, whereas that of KCNK3/TASK1 and KCNK6/TWIK2 channels was down-regulated. The similar up-regulated expression of KCNK1 and KCNK2 channels was observed in the pulmonary arterial smooth muscles of monocrotaline-induced PH rats, Sugen 5416/hypoxia-induced PH rats, and hypoxia-induced PH mice. The facilitated proliferation of IPAH-PASMCs was suppressed by the KCNK channel blockers, quinine and tetrapentylammonium. The migration of IPAH-PASMCs was also suppressed by these channel blockers. Furthermore, increases in the proliferation and migration were inhibited by the siRNA knockdown of KCNK1 or KCNK2 channels. The siRNA knockdown also caused membrane depolarization and subsequent decrease in cytosolic [Ca2+]. The phosphorylated level of c-Jun N-terminal kinase (JNK) was elevated in IPAH-PASMCs compared to normal-PASMCs. The increased phosphorylation was significantly reduced by the siRNA knockdown of KCNK1 or KCNK2 channels. Conclusion: Collectively, these findings indicate that the up-regulated expression of KCNK1 and KCNK2 channels facilitates the proliferation and migration of PASMCs via enhanced Ca2+ signaling and JNK signaling pathway, which is associated with vascular remodeling in PAH.

Prognostic significance of Ishii's sarcopenia screening score for patients undergoing curative surgery for obstructive colorectal cancer after intraluminal decompression.

PURPOSE: Sarcopenia influences the short- and long-term outcomes of various medical conditions including malignancy. Ishii's screening test estimates the probability of sarcopenia based on a score calculated by three simple variables: age, grip strength, and calf circumference. We investigated the clinical significance of Ishii's score for patients with non-metastatic obstructive colorectal cancer (OCRC) who underwent curative surgery after intraluminal decompression. METHODS: Ishii's score was calculated in 79 patients with OCRC. Muscle volume loss and decreased muscle quality were evaluated by computed tomography (CT) images as skeletal muscle index (SMI) and intramuscular adipose tissue content (IMAC), respectively. RESULTS: There were 46 men and 33 women, with a median age of 70 years old. The cutoff value for Ishii's score was 155.1 and 15 patients were in the high-score group. The high-score group was significantly associated with worse time to recurrence (TTR) and overall survival (OS), and a high Ishii's score was an independent negative prognostic factor for TTR (hazard ratio = 2.93, P = 0.015). A high Ishii's score was significantly associated with a low SMI value but not with the IMAC value. CONCLUSION: A high Ishii's score was independently associated with poorer TTR in patients with non-metastatic OCRC.

Pancreatic duct lavage cytology combined with a cell-block method for patients with possible pancreatic ductal adenocarcinomas, including pancreatic carcinoma in situ.

BACKGROUND/AIMS: This study aimed to clarify the efficacy and safety of pancreatic duct lavage cytology combined with a cell-block method (PLC-CB) for possible pancreatic ductal adenocarcinomas (PDACs). METHODS: This study included 41 patients with suspected PDACs who underwent PLC-CB mainly because they were unfit for undergoing endoscopic ultrasonography-guided fine needle aspiration. A 6-Fr double lumen catheter was mainly used to perform PLC-CB. Final diagnoses were obtained from the findings of resected specimens or clinical outcomes during surveillance after PLC-CB. RESULTS: Histocytological evaluations using PLC-CB were performed in 87.8% (36/41) of the patients. For 31 of the 36 patients, final diagnoses (invasive PDAC, 12; pancreatic carcinoma in situ, 5; benignancy, 14) were made, and the remaining five patients were excluded due to lack of surveillance periods after PLC-CB. For 31 patients, the sensitivity, specificity, and accuracy of PLC-CB for detecting malignancy were 94.1%, 100%, and 96.8%, respectively. In addition, they were 87.5%, 100%, and 94.1%, respectively, in 17 patients without pancreatic masses detectable using endoscopic ultrasonography. Four patients developed postprocedural pancreatitis, which improved with conservative therapy. CONCLUSION: PLC-CB has an excellent ability to detect malignancies in patients with possible PDACs, including pancreatic carcinoma in situ.

Low Geriatric Nutritional Risk Index (GNRI) Predicts Poorer Survival in Patients with Obstructive Colorectal Cancer Who Had a Self-Expandable Metallic Stent (SEMS) Inserted as a Bridge to Curative Surgery.

Objectives: The geriatric nutritional risk index (GNRI) is a nutrition-related risk index calculated easily from serum albumin and the ratio of body weight to ideal body weight. We investigated the prognostic values of the GNRI in elderly patients with obstructive colorectal cancer (OCRC) who had a self-expandable metallic stent inserted as a bridge to curative surgery. Methods: We retrospectively evaluated 61 patients aged ≥65 years with pathological stage I to III OCRC. Associations of preoperative GNRI and pre-stenting GNRI (ps-GNRI) with short- and long-term outcomes were examined. Results: Multivariate analyses revealed GNRI of <85.3 and ps-GNRI of <92.9 were independently associated with worse cancer-specific survival (CSS; P = 0.016, and P = 0.041, respectively), and overall survival (OS; P = 0.020, and P = 0.024, respectively). A ps-GNRI of <92.9 was correlated with poorer relapse-free survival (RFS) only in the univariate analysis (P = 0.034). For the OCRC cohort without age restriction (n = 86), GNRI of <85.3 and ps-GNRI of <92.9 were independently associated with worse CSS (P = 0.021), and OS (P = 0.023), respectively. In univariate analysis, ps-GNRI of <92.9 was significantly correlated with poorer RFS (P = 0.006). Moreover, ps-GNRI of <92.9 was significantly associated with Clavien-Dindo grade of ≥III postoperative complications (P = 0.037), anastomotic leak (P = 0.032), infectious complications (P = 0.002), and longer postoperative hospital stay (17 days vs. 15 days; P = 0.048). Conclusions: In OCRC patients, decreased preoperative and pre-stenting GNRI were significantly correlated with poorer survival, and decreased pre-stenting GNRI was significantly associated with worse short- and long-term outcomes.

Diagnostic value of homogenous delayed enhancement in contrast-enhanced computed tomography images and endoscopic ultrasound-guided tissue acquisition for patients with focal autoimmune pancreatitis.

BACKGROUND/AIMS: We aimed to investigate (1) promising clinical findings for the recognition of focal type autoimmune pancreatitis (FAIP) and (2) the impact of endoscopic ultrasound (EUS)-guided tissue acquisition (EUS-TA) on the diagnosis of FAIP. METHODS: Twenty-three patients with FAIP were involved in this study, and 44 patients with resected pancreatic ductal adenocarcinoma (PDAC) were included in the control group. RESULTS: (1) Multivariate analysis revealed that homogeneous delayed enhancement on contrast-enhanced computed tomography was a significant factor indicative of FAIP compared to PDAC (90% vs. 7%, p=0.015). (2) For 13 of 17 FAIP patients (76.5%) who underwent EUS-TA, EUS-TA aided the diagnostic confirmation of AIPs, and only one patient (5.9%) was found to have AIP after surgery. On the other hand, of the six patients who did not undergo EUS-TA, three (50.0%) underwent surgery for pancreatic lesions. CONCLUSION: Homogeneous delayed enhancement on contrast-enhanced computed tomography was the most useful clinical factor for discriminating FAIPs from PDACs. EUS-TA is mandatory for diagnostic confirmation of FAIP lesions and can contribute to a reduction in the rate of unnecessary surgery for patients with FAIP.

Prospective feasibility study on the efficacy and safety of a novel spiral dilator for endoscopic ultrasound-guided drainage.

Objectives: A difficult step in endoscopic ultrasound (EUS)-guided drainage procedures is dilation of the puncture tract before stent deployment. The efficacy and safety of a novel spiral dilator, Tornus ES, for EUS-guided drainage were investigated in this study. Methods: This study was conducted as a prospective, single-arm, observational study at Sendai City Medical center. Dilation of the puncture tract using a spiral dilator was attempted for all EUS-guided drainage cases. The primary outcome was the technical success rate which was defined as successful stent placement in the puncture tract. Secondary outcomes were the success rate of dilation using a spiral dilator, procedure time, and adverse events related to the procedures. Results: A total of 10 patients were enrolled between January and March 2022. Seven patients underwent EUS-guided biliary drainage (hepaticogastrostomy for six and hepaticojejunostomy for one), and the remaining three patients underwent EUS-guided gallbladder drainage. The technical success rate and the success rate of dilation using a spiral dilator were both 100%. The mean procedure time was 27 min. No adverse events related to the procedure occurred in all cases. Conclusions: Dilation of the puncture tract using a spiral dilator was effective and safe and might make it easier to perform EUS-guided drainage.

Treatment Strategy for Acute Cholecystitis Induced by a Metallic Stent Placed in Malignant Biliary Strictures: Role of Percutaneous Transhepatic Gallbladder Aspiration.

Objective The present study evaluated the strategic role of percutaneous transhepatic gallbladder aspiration (PTGBA) for acute cholecystitis (AC) induced by a metallic stent (MS) placed in a malignant biliary stricture in comparison with percutaneous transhepatic gallbladder drainage (PTGBD). Methods The treatment outcomes for 31 patients who underwent PTGBA as the initial intervention for MS-induced AC were evaluated and compared with those for 12 who underwent PTGBD. Results The technical success rate was 100% for both groups. PTGBA was ineffective for 11 patients, all of whom recovered with additional intervention, whereas PTGBD was effective for all patients except for 1 who died of sepsis (clinical success rate, 65% vs. 90%, p=0.16). Adverse events (AEs) were observed in only 1 case (3%) in the PTGBA group (mild bile peritonitis). Among the clinically effective cases, AC recurred in 20% of the PTGBA group and 33% of the PTGBD group (p=0.72). In the PTGBA group, the clinical success rate was significantly higher for patients without cancer invasion to a feeding artery of the gallbladder than in those with invasion (75% without invasion vs. 29% with invasion; p=0.036). According to the multivariate analysis, this factor was an independent factor for clinical success of PTGBA (odds ratio, 9.27; p=0.040). Conclusion Although the clinical success rate of PTGBA for MS-induced AC was lower than that of PTGBD, PTGBA remains a viable option because of its safety and procedural simplicity, especially for cases without tumor invasion to a feeding artery.

A decreased preoperative platelet-to-lymphocyte ratio, systemic immune-inflammation index, and pan-immune-inflammation value are associated with the poorer survival of patients with a stent inserted as a bridge to curative surgery for obstructive colorectal cancer.

PURPOSE: Inflammation is one of the hallmarks of cancer, and inflammation-based markers that are calculated easily from laboratory results have shown predictive abilities. We investigated the prognostic values of the preoperative platelet-to-lymphocyte ratio (PLR), systemic immune-inflammation index (SII), and pan-immune-inflammation value (PIV) in patients with non-metastatic obstructive colorectal cancer (OCRC) and a self-expandable metallic stent inserted as a bridge to curative surgery. METHODS: The subjects of this retrospective study were 86 patients with pathological stage I to III OCRC. We examined the associations of these biomarkers with short- and long-term outcomes. RESULTS: Multivariate analyses revealed that a preoperative PLR < 149, SII < 597, and PIV < 209 were independently associated with poorer relapse-free survival (RFS) (P = 0.007, P < 0.001, and P = 0.002, respectively) and that a PIV < 209 was independently associated with poorer cancer-specific survival (P = 0.030). A platelet count < 240 was significantly associated with worse RFS, whereas the lymphocyte count was not. Pre-stenting PLR < 221 was an independent poor prognostic factor for RFS (P = 0.045). CONCLUSION: This study showed that decreased preoperative PLR, SII, PIV, and pre-stenting PLR were associated with poorer RFS, contrary to the findings of most previous studies. Our results suggest that platelets and obstruction contributed primarily to the opposite relationships, which might provide new insight into the possible pathophysiology of platelet-tumor interactions generated in the OCRC environment.

Prognostic significance of the mean corpuscular volume (MCV) and red cell distribution width (RDW) in obstructive colorectal cancer patients with a stent inserted as a bridge to curative surgery.

PURPOSE: The prognostic significance of the mean corpuscular volume (MCV) and red cell distribution width (RDW) in patients with malignancy have not been intensely investigated and are largely overlooked. We, therefore, investigated the clinical significance of MCV and RDW in non-metastatic obstructive colorectal cancer (OCRC) patients with a self-expandable metallic stent inserted as a bridge to curative surgery. METHODS: Eighty-five pathological stage II and III OCRC patients were retrospectively evaluated. The associations of the preoperative MCV and RDW values with short- and long-term outcomes were examined. RESULTS: There were 50 males and 35 females, and the median age was 71 years old. The median interval between stenting and surgery was 17 days, and the median postoperative hospital stay was 16 days. Fifty-six patients were in the MCV ≥ 87 group, and 47 were in the RDW ≥ 13.8 group. Multivariate analyses revealed the MCV ≥ 87 status to be independently associated with a poor relapse-free survival (hazard ratio [HR] = 4.70, 95% confidence interval [CI] 1.52-14.58, P = 0.007). The RDW ≥ 13.8% was an independent predictor of postoperative infectious complications (HR = 7.28, 95% CI 1.24-42.70, P = 0.028). CONCLUSION: The MCV and RDW are simple but strong predictors of postoperative outcomes in OCRC patients.

Impact of Sarcopenia on Postoperative Complications in Obstructive Colorectal Cancer Patients Who Received Stenting as a Bridge to Curative Surgery.

OBJECTIVES: Understanding the relationship between sarcopenia and malignancy is increasingly important since they inevitably affect the aging population. We investigated the clinical significance of sarcopenia in nonmetastatic obstructive colorectal cancer (OCRC) patients who were inserted self-expandable metallic stent and underwent curative surgery. METHODS: Plain cross-sectional CT images obtained before stenting were retrospectively analyzed in 92 patients. Muscle volume loss (myopenia) and decreased muscle quality (myosteatosis) were evaluated as skeletal muscle index (SMI) and intramuscular adipose tissue content (IMAC), respectively. RESULTS: This study included 54 men and 38 women, with a median age of 70.5 years. The median interval between SEMS placement and the surgery was 17 days (range, 5-47). There were 35 postoperative complications. The median postoperative hospital stay was 15.5 days (range, 8-77). Twenty-eight patients (41.3%) were classified as SMI-low, and 31 (34.1%) patients were classified as IMAC-high. In multivariate analysis, IMAC-high [hazard ratio (HR) = 7.68, 95% confidence interval (CI) 2.22-26.5, P = 0.001] and right-sided tumor (HR = 5.79, 95% CI 1.36-24.7, P = 0.018) were independent predictors of postoperative complications. IMAC-high (HR = 23.2, 95% CI 4.11-131, P < 0.001) and elevated modified Glasgow prognostic score (mGPS) (HR = 5.85, 95% CI 1.22-28.1, P = 0.027) were independent predictors of infectious complications. Relapse-free survival and overall survival were not significantly different regardless of the SMI or IMAC status. CONCLUSIONS: IMAC was associated with postoperative complications and infectious complications. Myosteatosis might be a stronger predictor of postoperative complications than myopenia.

A longer interval after stenting compromises the short- and long-term outcomes after curative surgery for obstructive colorectal cancer.

PURPOSE: Intestinal decompression using self-expandable metallic colonic stents (SEMSs) as a bridge to surgery is now considered an attractive alternative to emergency surgery. However, data regarding the optimal timing of surgery after stenting are limited. METHODS: We investigated the impact of the interval between stenting and surgery on short- and long-term outcomes in 92 obstructive colorectal cancer (OCRC) patients who had a SEMS inserted and subsequently received curative surgery. RESULTS: The median age of the patients was 70.5 years, and the median interval between SEMS insertion and the surgery was 17 (range 5-47) days. There were 35 postoperative complications, including seven major postoperative complications. An interval of more than 16 days was an independent predictor of a poor relapse-free survival (hazard ratio [HR] = 3.12, 95% confidence interval [CI] 1.24-7.81, p = 0.015). An interval of more than 35 days was independently associated with major postoperative complications (HR = 16.6, 95% CI 2.21-125, p = 0.006). CONCLUSION: A longer interval between stenting and surgery significantly compromised the short- and long-term outcomes. Surgery within 16 days after stenting might help maximize the benefit of SEMS without interfering with short- and long-term outcomes.

Accurate endoscopic identification of the afferent limb at the Y anastomosis using the fold disruption sign after gastric resection with Roux-en-Y reconstruction.

In patients with Roux-en-Y (RY) reconstruction for gastric resection, the newly defined "fold disruption" (FD) sign can be useful to distinguish the afferent limb from the efferent limb at the Y anastomosis when balloon endoscopy-assisted endoscopic retrograde cholangiopancreatography (BE-ERCP) is performed. The FD sign was defined as endoscopic findings of the internal folds disrupted toward the afferent limb and continued toward the efferent limb at the Y anastomosis. In this prospective observational study, the accuracy of the FD sign was evaluated for those who underwent BE-ERCP after gastric resection with RY reconstruction. Of 28 patients for whom the accuracy could be evaluated among 30 enrolled patients, the afferent limb was identified using the FD sign with 100% accuracy. For the other two patients, the scope could not reach the target lumen due to severe intestinal adhesion in one and reached the target lumen without recognition of the Y anastomosis in the other. There was no patient for whom the FD sign could not be judged for any reason, such as a blurred anastomosis line, unclear folds, sticky discharge and blood coating the surface, when the Y anastomosis was recognized. The FD sign was a highly accurate tool for distinguishing the afferent limb from the efferent limb in patients after gastric resection with RY reconstruction. This study was registered in UMIN (issued ID, UMIN000038326).

Early and long-term clinical outcomes of endoscopic interventions for benign pancreatic duct stricture/obstruction-the possibility of additional clinical effects of endoscopic ultrasonography-guided pancreatic drainage.

OBJECTIVES: For benign pancreatic duct strictures/obstructions (BPDS/O), endoscopic ultrasonography-guided pancreatic drainage (EUS-PD) is performed when endoscopic transpapillary pancreatic drainage (ETPD) fails. We clarified the clinical outcomes for patients with BPDS/O who underwent endoscopic interventions through the era where EUS-PD was available. METHODS: Forty-five patients with BPDS/O who underwent ETPD/EUS-PD were included. We retrospectively investigated overall technical and clinical success rates for endoscopic interventions, adverse events, and clinical outcomes after successful endoscopic interventions. RESULTS: The technical success rates for ETPD and EUS-PD were 77% (35/45) and 80% (8/10), respectively, and the overall technical success rate using two drainage procedures was 91% (41/45). Among the 41 patients who underwent successful endoscopic procedures, the clinical success rates were 97% for the symptomatic patients (35/36). The rates of procedure-related pancreatitis after ETPD and EUS-PD were 13% and 30%, respectively. After successful endoscopic interventions, the cumulative 3-year rate of developing recurrent symptoms/pancreatitis was calculated to be 27%, and only two patients finally needed surgery. Continuous smoking after endoscopic interventions was shown to be a risk factor for developing recurrent symptoms/pancreatitis. CONCLUSIONS: By adding EUS-PD to ETPD, the technical success rate for endoscopic interventions for BPDS/O was more than 90%, and the clinical success rate was nearly 100%. Due to the low rate of surgery after endoscopic interventions, including EUS-PD, for patients with BPDS/O, EUS-PD may contribute to their good clinical courses as a salvage treatment for refractory BPDS/O.

Prognostic Significance of Preoperative Globulin-to-albumin Ratio in Obstructive Colorectal Cancer Patients Who Underwent Curative Surgery after Stenting.

OBJECTIVES: It has been increasingly recognized that the progression of cancer is dependent not only on the tumor characteristics but also on the nutritious and inflammatory condition of the host. We investigated the relationship between the globulin-to-albumin ratio (GAR) and long-term outcomes in obstructive colorectal cancer (OCRC) patients who were inserted self-expandable metallic stent as a bridge to curative surgery. METHODS: A total of 75 pathological stage II and III OCRC patients between 2013 and 2020 were retrospectively evaluated. The associations of the preoperative GAR with clinicopathological factors and patient survival were examined. RESULTS: Receiver operating characteristic curve analysis demonstrated that the optimal cutoff value was 0.88. The GAR ≥ 0.88 status was significantly associated with the absence of lymph node metastasis (P = 0.011), longer postoperative hospital stay (17 days vs 15 days, P = 0.042), and not receiving adjuvant chemotherapy (P = 0.011). Relapse-free survival and cancer-specific survival were significantly shorter in the GAR ≥ 0.88 group (P = 0.007 and P = 0.023, respectively). Multivariate analyses revealed that the GAR ≥ 0.88 was independently associated with relapse-free survival [hazard ratio (HR) = 4.17, 95% confidence interval (CI) 1.32-13.14, P = 0.015)]. Moreover, CA19-9 ≥ 37 (HR = 6.56, 95% CI 2.12-20.27, p = 0.001) and not receiving adjuvant chemotherapy (HR = 4.41, 95% CI 1.28-15.26, p = 0.019) were independent poor prognostic factors for relapse-free survival. CONCLUSIONS: The results demonstrated that the GAR was a significant prognostic factor for OCRC patients.

Pancreatic Ductal Adenocarcinoma Concomitant with Main Duct Type Intraductal Papillary Mucinous Neoplasm of the Pancreas: A Case Report.

BACKGROUND Intraductal papillary mucinous neoplasm of the pancreas (IPMN) and pancreatic ductal adenocarcinoma (PDAC) often coexist in the same pancreas. Almost all IPMNs involving PDACs concomitant with IPMN have been shown to be branch duct type IPMNs (BD-IPMNs), and their histological subtypes are gastric type. Therefore, PDACs concomitant with main duct type IPMNs (MD-IPMNs) are considered to be rare. We herein report a rare case preoperatively diagnosed as being a PDAC concomitant with MD-IPMN on the basis of imaging findings and histological findings of pancreatic specimens endoscopically obtained from 2 lesions. CASE REPORT A 67-year-old man was referred to our hospital due to an enlarged pancreas. Using imaging studies, a solid mass was found in the pancreatic head and intraductal papillary masses in the dilated main pancreatic duct of the body and tail with a fistula in the duodenum. On the basis of histological results using specimens endoscopically obtained from each of the 2 lesions, total pancreatectomy was planned due to suspected PDAC concomitant with an MD-IPMN. Finally, resected specimens were used to confirm the presence of a rare case of PDAC concomitant with MD-IPMN. CONCLUSIONS We encountered a rare case of a PDAC concomitant with an MD-IPMN which could be preoperatively diagnosed by using imaging studies and histological specimens endoscopically obtained. In addition to invasive cancers derived from IPMNs, PDACs concomitant with IPMNs can rarely develop in the pancreas involving MD-IPMNs.